Glass vacuum tubes have been widely used in audio applications such as amplification of musical instruments as well as hi-fidelity reproduction. Although solid-state circuit technology has also been developed for use in such audio applications, traditional glass-envelope vacuum tubes are still being used in some audio applications. Modern audio applications often use glass vacuum tubes for their acoustic properties, as well as their esthetic appeal.
Solid-state technology has been acknowledged for cost, performance, manufacturability, and/or other advantages over glass vacuum tubes. Solid-state devices can be significantly less expensive to manufacture, smaller in size, less prone to mechanical failures and wear-out anomalies as compared to glass vacuum tubes. Some solid-state systems and implementations have been developed to emulate the overall functional operation of a glass vacuum tube.
Direct pin-for-pin compatible vacuum tube replacement devices (VTRDs) have also been developed such as is described by the present author in U.S. patent application Ser. No. 11/678,562, titled “VACUUM TUBE REPLACEMENT DEVICE, CIRCUIT AND SYSTEM”. The present disclosure describes solid-state circuits that can be incorporated into VTRDs to effectively emulate the functions of traditional glass-envelope vacuum tubes with greatly expanded functionality beyond that available in conventional glass vacuum tube devices. As will be further described, the present disclosure contemplates applying the described system, circuits and devices in other non-vacuum tube replacement applications.